Khan is only 21 years old. That's still very very young. It doesn't matter how many years he's been pro. If he had turned pro at 22 and still wasn't a titleholder after 4 years, that would be an issue, but that's not the case here.
It is a red flag that he's getting knocked down, but it's important to note that when he's gotten knocked down, he's picked himself up and knocked out his opponent.
Khan has work to do, but he still has the potential to be a great fighter.
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